Open top range and associated gas distribution system

ABSTRACT

A gas range includes a plurality of open-top burners and a gas distribution system for controlling gas feed to the open-top burners. The gas distribution system includes a primary manifold and a plurality of secondary manifolds. Each secondary manifold is connected to feed gas to one or more of the open-top burners. Each secondary manifold is connected to receive gas from the primary manifold through a respective safety shut-off device such that gas feed from the primary manifold to each secondary manifold is controlled independently of gas feed from the primary manifold to any other secondary manifold. The primary manifold and each secondary manifold may be configured as modular assemblies.

TECHNICAL FIELD

This application relates generally to open top gas ranges and, morespecifically, to a gas distribution system for an open top gas range.

BACKGROUND

Commercial gas ranges typically include multiple open top burnersindividually actuated by low-cost, mechanical throttle valves. Burnerignition has historically been achieved through standing pilots, inwhich gas is continuously dispersed at the pilot source regardless offlame presence. The high volume, low-cost, and open top nature of thistraditional set-up, along with commercial kitchen ventilationrequirements, has generally obviated any widespread adoption of flamesensing technology, as currently required in range ovens and otherstyles of commercial and residential cooking equipment.

However, stricter regulations, both in US and abroad, along with growingcustomer preference for 100% monitoring of open source flames, hasincreased demand for a scalable, cost-effective solution. Severalmechanisms are available for sensing flame and controlling gas flow, butadoption to the rigors and high-BTU output of commercial open top burneroperation has not been readily accomplished.

Commercial gas ranges typically distribute fuel gas through rigid pipeconduit manifolds. Manifolds may be continuous pieces of straight orbent pipe or may consist of multiple sections of pipe joined withconventional pipe fittings. Other embodiments include square orrectangular tubing. The primary function is to distribute the incominggas to various range appliances such as open-top burners, griddles, andovens, among other items.

Gas is distributed from manifolds to open-top burner assemblies throughlow-cost throttle valves, typically brass with threaded pipe endconnections. These simple and reliable designs are capable of high flowrates and demanding operating environments. Likewise, gas can bedistributed to standing pilots directly from manifolds throughbleed-type valves, also brass and configured with threaded pipe endconnections.

For years, the cooking industry has adopted stricter requirements andincreased customer preference for safety control on gas appliances,particularly in residential markets. This has driven innovations inall-in-one combination gas valves, or valves that are configured withthermo-electric safety shut-off devices inside, along with manualthrottling control. The main advantage of this set-up is space savingsand fewer assembly steps. In other embodiments, the combination valvesalso contain pilot bleed-off ports, eliminating the need for astandalone pilot valve mounted on the manifold. One disadvantage forthese types of set-ups is cost. In some cases, the cost for thecombination valve set-up can be more than ten times the cost of alow-cost throttle valve. While this trade-off may be desirable incertain applications, particularly for single-burner applications orlocations expected to require little or no servicing, the added costpresents a dilemma for large multi-burner set-ups prone to heavy usageand corresponding servicing.

The combination valve set-up also compromises efficiencies gained whenconvenient pilot flash tubes are used on burner assemblies. The pilotflash tube allows one standing pilot to ignite two or more burnerassemblies. When combination valves are used, thermo-electric powerneeds to either be split to two separate valves, or an additional pilotflame source needs to be created. An alternative to any of the statedset-ups is digital control and automatic ignition sources; however,these are not considered fully adapted to commercial open-top burneruse, and they do not permit the benefit of analog, or un-plugged,operation. Also, a combination valve or safety device (commonlypush-button) dedicated for each burner will require twice as manylighting procedures as a set-up that is adapted to a flash tube pilotsystem. For large open-top burner set-ups, sometimes ten or twelve perassembly, this represents a significant amount of time and effort,possibly routine depending on night-time shut-down procedures, simplyfor lighting pilots.

What is needed is a gas distribution system with simple safety shut-offdevices incorporated such that cost and design efficiencies of existinggas control valves, burner assemblies, and flash tube designs can bepreserved. The system should desirably fit within existing spaceenvelopes, permit ready servicing from the front of the assembly, and/orallow gas-supply connections to continue to be made for non-“open-top”appliances (e.g., an oven or griddle). The inventive system disclosedherein meets these objectives and can be considered applicable to anyfront-manifold, flash tube system of conventional open-top burnerranges.

SUMMARY

In one aspect, a gas range includes a plurality of open-top burners anda gas distribution system for controlling gas feed to the open-topburners. The gas distribution system includes a primary manifold and aplurality of secondary manifolds. Each secondary manifold is connectedto feed gas to one or more of the open-top burners. Each secondarymanifold is connected to receive gas from the primary manifold through arespective safety shut-off device such that gas feed from the primarymanifold to each secondary manifold is controlled independently of gasfeed from the primary manifold to any other secondary manifold.

In another aspect, a gas range includes a gas distribution systemincluding a primary manifold, first and second secondary manifolds, andfirst and second safety shut-off devices. The first secondary manifoldis connected to receive gas from the primary manifold through the firstsafety shut-off device. The second secondary manifold is connected toreceive gas from the primary manifold through the second safety shut-offdevice.

In a further aspect, a gas distribution system is provided for a gasrange including multiple open-top burners. The gas distribution systemincludes a primary manifold, first and second secondary manifolds, andfirst and second safety shut-off devices. The first secondary manifoldis connected to receive gas from the primary manifold through the firstsafety shut-off device. The second secondary manifold is connected toreceive gas from the primary manifold through the second safety shut-offdevice.

The details of one or more embodiments are set forth in the accompanyingdrawings and the description below. Other features, objects, andadvantages will be apparent from the description and drawings, and fromthe claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of a commercial gasrange;

FIG. 2 is an exploded perspective view of a gas feed system of the rangeof FIG. 1;

FIG. 3 is an assembled perspective view of the gas feed system;

FIG. 4 is a top plan view of the gas feed system;

FIG. 5 is a partial front elevation of the range of FIG. 1;

FIGS. 6A-6C show front elevation views of alternative feed systems fordifferent numbers of open-top burners.

DETAILED DESCRIPTION

With significant cost, operation, and manufacturing/servicing benefits,the subject design described below, with reference to one or morespecific embodiments, introduces a more valuable method for monitoringopen-top burners and their pilots.

Referring to FIG. 1, an exemplary open-top gas range 10 is shown. In theillustrated embodiment four burners 12 are provided atop a range housingthat incorporates a gas oven accessible by a door 16, but variations arepossible, such as two burner arrangements, six burner arrangements,eight burner arrangements etc. Each burner may typically be covered by arespective, removable cookware support grate 14, but only two grates areshown in FIG. 1.

FIG. 2-4 show a gas feed system 20 of the range (but with only two ofthe burners 12 instead of four depicted). In the exploded view of FIG. 2the modular nature of the overall system 20 is best seen. In thisregard, a primary manifold assembly 22 includes a primary manifold 24,here L-shaped with a gas inlet port 26 located at a rear portion of themanifold that extends toward a back of the oven. The primary manifoldassembly 22 also includes a gas control valve 28 mounted along thefront, lateral leg of the manifold for delivering fuel gas from anoutlet port of the primary manifold to a component of the applianceother than the open-top burners, which in the case of the range 10 ofFIG. 1 would be the oven. Mounting brackets 30 are welded or otherwiseattached to the primary manifold 24 in order to secure the primarymanifold to a frame of the range. Additional mounting brackets could beprovided as needed. A feed valve 31 to the oven pilot is also shown.

A pair of safety shut-off devices 32 are also mounted to the front,lateral leg of the primary manifold 24 at spaced apart locations fromeach other, here on opposite sides of the location of the gas controlvalve 28, for delivering fuel gas from respective outlet ports of theprimary manifold to respective secondary manifold assemblies 34 thatconnect to the safety shut-off devices. Each safety shut-off device 32may, by way of example, be a push-button thermo-electric valve thatutilizes a feedback voltage from a thermocouple 36 (e.g., see the dashedline connection in FIG. 4) to maintain the valve in an open conditionwhen pilot flame is detected, and likewise the valve closes by defaultwhen pilot flame is not detected.

Each secondary manifold assembly 34 includes a secondary manifold 40with an adapter 38 connected to an inlet port of the secondary manifoldfor making the connection to a safety shut-off device 32 of the primarymanifold. A set of mounting brackets 42 and 44 are provided forsupporting the secondary manifold on the frame of the range. A pair ofopen-top burner valves 46 (one for each of the burners 12) are mountedto respective outlet ports of the secondary manifold 40 enablingindividual, manual burner control. A pilot valve 48 (e.g., bleed-type)connects to another outlet port of the secondary manifold 40 to feed gasto a pilot burner 50 of the gas burner assembly 52. The secondarymanifold 40 may include an additional outlet port closed by a plug 54.

Each burner assembly 52 (only one being shown) includes a venturicasting, two burner heads 12, air intake shutters, and a flash tube 64for delivering the pilot flame to each burner head. A pilot assembly 60is located between the burners, where the pilot assembly includes thepilot burner 50, an optional pilot starter 62 (e.g., a piezo igniteractivated by a push-button or rotary knob), the thermocouple 36 and atee-pilot hood 66. In one implementation, the starter of each pilotassembly may be triggered by the same manual actuator.

In the illustrated embodiment, the secondary manifold assemblies 34 aresubstantially identical in size and shape. Both secondary manifolds 40are substantially aligned along a common horizontal axis. However,separate gas control shut-off devices 32 provide the gas feed connectionfrom the primary manifold to each secondary manifold. As shown, theprimary and secondary manifolds may exhibit intentional shaping andbends in order to preserve linear relationships and to facilitate totalsystem modularity.

In a method of assembly of the gas feed system, the primary manifoldassembly 22 is first assembled with safety shut-off devices 32 (in thisexample, push-button thermoelectric valves) and one or morenon-“open-top” burner devices (e.g., oven thermostat, tube fitting,plug). The secondary manifold assemblies 34 are assembled, each with twoopen-top burner valves 46, a pilot valve 48, a plug 54, and an adapter38. The primary and secondary manifold assemblies are then mounted ontoa range body using the attached mount brackets. The adapters 38 slideinto compression tube fittings on the safety shut-off devices 32,enabling easy assembly by rotating the compression nut (e.g., 70)provided on each safety shut-off device 32. This method of assembly,while just one example, permits isolated servicing and replacement ofindividual secondary manifolds and safety shut-off devices withoutremoving other manifolds (e.g., referring to FIG. 3, the left secondarymanifold assembly 34 can be removed without removal of the rightsecondary manifold assembly 34, and vice versa). In other methods ofassembly, the safety shut-off devices 32 could be first attached to thesecondary manifold assemblies, then joined directly or by other tubing,rigid or flex or otherwise, to the primary manifold 24.

From an operational standpoint, each shut-off device 32 controls whethergas will flow from an outlet port of the primary manifold 24 into oneassociated secondary manifold 40. Thus, a given shut-off device 32 actsas a main control as to whether gas can flow to any of the pilot burner50 or the two the two open-top burners 12 of a burner assembly 52 thatis connected to the secondary manifold 40 fed by the shut-off device 32.

To start a given pilot burner 50, the push-button 32′ of the shut-offdevice is actuated from the front of the range 10 (see FIG. 5), whichfeeds gas into the secondary manifold 40 and through the pilot valve 48to the pilot burner 50. The igniter 62 is actuated (e.g., using a rotaryactuator 72 at the front of the range). When the pilot burner 50 starts,the voltage feeback from the thermocouple 36 maintains the shut-offdevice open. The same process can be used to start the pilot burner ofany other burner assemblies connected to the primary manifold 24 throughrespective secondary manifold assemblies. If the pilot burner of a givenburner assembly 52 becomes extinguished, the thermocouple voltagefeedback ceases causing the shut-off device 32 feeding that burnerassembly 52 to close. However, the shut-off devices 32 feeding otherburner assemblies operate independently and may remain open.

Referring to FIG. 5, valve knobs 80 for the open-top burners are shown,along with the valve knob 82 for the oven feed valve. A front gascontrol panel 84 on the range body includes spaced apartcutouts/openings 86, and each opening 86 is shared by the pair of burnercontrol valves and the safety shut-off device of a given secondarymanifold assembly. Thus, a separate cutout is provided for eachsecondary manifold assembly.

FIGS. 6A-6C shows potential alternative gas feed systems 20, 20′ and 20″with alternate lengths of primary manifolds and corresponding varyingnumbers of secondary manifolds, where system 20′ includes a singlesecondary manifold assembly (e.g., for a two-top burner arrangement),system 20 includes two secondary manifold assemblies as primarilydescribed above and system 20″ includes three secondary manifoldassemblies (e.g., for a six-top burner arrangement). For construction ofcommercial ranges, open-top burners and other appliances are commonlyspecified in section widths of 12 inches. The subject gas feed systemsmay be designed accordingly for a 12-inch range, 24 inch range and 36inch range, but this is not a requirement. The spacing between any twoadjacent secondary manifold assemblies is nearly equal in the system 20″of FIG. 6C. In the system 20′ of FIG. 6B, the spacing between secondarymanifold assemblies may be similar to that of FIG. 6C, but may also beintentionally maximized to permit installation of a non-“open-top”burner valve.

As used herein, the terminology “outlet port” of a manifold can bedefined as a dedicated opening in the pipe or conduit, or by extension,through a tee or similar style fitting known in the art for convenientlysplitting fluid flow, in which case each terminal of the tee orfitting(s) can be defined as an outlet port of the manifold.

It is to be clearly understood that the above description is intended byway of illustration and example only, is not intended to be taken by wayof limitation, and that other changes and modifications are possible.

What is claimed is:
 1. A gas range, comprising: a plurality of open-topburners; a gas distribution system for controlling gas feed to theopen-top burners, the gas distribution system including: a primarymanifold, a plurality of secondary manifolds, each secondary manifoldconnected to feed gas to one or more of the open-top burners, eachsecondary manifold connected to receive gas from the primary manifoldthrough a respective safety shut-off device such that gas feed from theprimary manifold to each secondary manifold is controlled independentlyof gas feed from the primary manifold to any other secondary manifold.2. The range of claim 1, wherein: each secondary manifold has an inletport and at least one outlet port, for each secondary manifold, therespective safety shut-off device couples an outlet port of the primarymanifold to the inlet port of the secondary manifold.
 3. The range ofclaim 1 wherein each secondary manifold is substantially aligned along acommon axis.
 4. The range of claim 3 wherein each secondary manifold issubstantially identical in size and shape.
 5. The range of claim 3wherein a linear distance between any two adjacent secondary manifoldsis substantially equal.
 6. The range of claim 1 wherein each secondarymanifold includes at least two burner control valves for feedingrespective open-top burners.
 7. The range of claim 6 wherein eachsecondary manifold includes at least one pilot control valve.
 8. Therange of claim 7 wherein each pilot control valve delivers gas to arespective pilot burner, for each pilot burner: a thermocouple isassociated with the pilot burner, and the thermocouple controls anopen/closed state of the safety shut-off device that feeds gas to thesecondary manifold that feeds the pilot burner.
 9. The range of claim 4wherein a separate gas control valve is located on the primary manifoldbetween a pair of adjacent secondary manifolds.
 10. The range of claim 2wherein at least one secondary manifold can be removed from the rangeindependent of removal of any other secondary manifold.
 11. The range ofclaim 10 wherein at least one safety shut-off device can be removed fromthe range independent of removal of any other safety shut-off device.12. The range of claim 1, further comprising a gas control panel,wherein two open-top burner control valves and one safety shut-offdevice are located on a common secondary manifold and share onecontinuous cut-out in the gas control panel.
 13. A gas range,comprising: a gas distribution system including a primary manifold,first and second secondary manifolds, and first and second safetyshut-off devices, wherein: the first secondary manifold is connected toreceive gas from the primary manifold through the first safety shut-offdevice, and the second secondary manifold is connected to receive gasfrom the primary manifold through the second safety shut-off device. 14.The range of claim 13 wherein: the primary manifold has an inlet portand at least first and second outlet ports, the first secondary manifoldhas an inlet port and multiple outlet ports, the second secondarymanifold has an inlet port and multiple outlet ports, the first safetyshut-off device couples the first outlet port of the primary manifold tothe inlet port of the first secondary manifold, the second safetyshut-off device couples the second outlet port of the primary manifoldto the inlet port of the second secondary manifold.
 15. The range ofclaim 14 wherein the first secondary manifold includes a first pilotfeed valve, and the second secondary manifold includes a second pilotfeed valve.
 16. The range of claim 15 wherein: the first pilot feedvalve delivers gas to a first pilot burner, a first thermocouple isassociated with the first pilot burner, and the first thermocouplecontrols an open/closed state of the first safety shut-off device; thesecond pilot feed valve delivers gas to a second pilot burner, a secondthermocouple is associated with the second pilot burner, and the secondthermocouple controls an open/closed state of the second safety shut-offdevice.
 17. The range of claim 16 wherein: the first pilot burner isarranged for igniting a first pair burners via a first flash tubearrangement; the second pilot burner is arranged for igniting a secondpair of burners via a second flash tube arrangement.
 18. A gasdistribution system for a gas range including multiple open-top burners,the gas distribution system comprising: a primary manifold, first andsecond secondary manifolds, and first and second safety shut-offdevices, wherein: the first secondary manifold is connected to receivegas from the primary manifold through the first safety shut-off device,and the second secondary manifold is connected to receive gas from theprimary manifold through the second safety shut-off device.
 19. Thesystem of claim 18 wherein: the first secondary manifold includes afirst pilot feed valve; the second secondary manifold includes a secondpilot feed valve; the first pilot feed valve delivers gas to a firstpilot burner, a first thermocouple is associated with the first pilotburner, and the first thermocouple controls an open/closed state of thefirst safety shut-off device; the second pilot feed valve delivers gasto a second pilot burner, a second thermocouple is associated with thesecond pilot burner, and the second thermocouple controls an open/closedstate of the second safety shut-off device.